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How to use software Spectrum
Analyzers like HamAlyzer
Notice
I no longer use HamAlyzer
I could not get it to work with Vista. So I
will not be able to help you use it in any way. I can not contact Dan
Brown who is the owner of the software. He has not returned my emails.
As far as I know the product is still marketed and may work with Windows
Vista but I was not successful and thus I am of little help in setting
it up or debugging any problems you may be having. Many have contacted
me for help and I am not able to do so anymore. I do not have the
product on any of my computers at this time.
This
is a typical display (fig
1. ) using
the HamAlyzer spectrum
analyzer software package. The ham who I captured here was 59+10 or
so, at my station, so I had no problems copying him. I did 2 scans on him
and they were both almost the same as the one shown here. I know
this ham's normal voice and I would describe the audio he was projecting
as being kind of robotic and nasal. I am not saying that everyone
wants to sound like CBS or NBC, but unless you are trying to cut through a
DX pileup, this audio is kind of hard to listen to for a long time. Look
at the display below and observe where most of his energy starts and where
it ends. Freq 1(his bottom end) is 355Hz and Freq 2 (his high end) is
2368Hz. or an effective bandpass of 2013Hz. His radio is set up correctly,
and he is using a standard microphone that came with the rig he is using.
What could he do to make his audio better
after looking at this chart?

fig 1
The radio he is
using is a newer model DSP type radio with all the bells and whistles. It
has plenty of menu selections to make him sound better. He has
selected a very narrow filter which is fine for DX work, but is this
appropriate for talking to your buddies when you are 59+ coast to coast?
Smooth pleasant sounding audio is balanced and should use most of the
spectrum that your radio is capable of passing. This particular radio has
the ability to pass 3000Hz, but the ham is only using 2013Hz. What about
the remaining 987Hz? What about the spikes and valleys in this signal?
Wouldn't it sound better if they were smoothed out? Look at the big
spike at about 2200Hz? In general, the chart should start at a point on
the left and have a very slight slope to the right without any big spikes
or valleys. A lot of energy at the high end makes for a tinny sound, if
there is no balance on the low end. An over abundance of bottom end energy
can also make for a booming sound that is just as bad. Key word balance.

fig. 2
Here is a graph
(fig. 2) done
on a ham who is using an ICOM 775 with outboard audio processing
equipment. As you can see, almost all bandpass of this radio is
being utilized. His bottom end is at about 96Hz and his top end is at
approximately 3000Hz plus or minus a little. Now this is pretty good in
that the radio is not supposed to go beyond 2.9Hz on the top end. The
little extra is called EQ push. To make the sound better in my mind, he
could bring the top end down a little so that the slope was in there, but
this is typically what you can do with the proper settings and equipment.
Believe me this ham has spend a lot of time speaking into his dummy load
while doing many graphs of his audio. He is proud of it and he should be
so. There are some little peaks and valleys, but noting to extreme.
You could listen to him all night and it would be as though he was setting
in your living room or you were listening to him on a commercial radio
station. Would you want to listen to a commercial radio station that
sounded like the ham in fig.
1? I don't think
so.

fig. 3
This picture, fig. 3 shows
another way of using a spectrum analyzer package to compare different
signals using the "Overlay" feature that is part of most
analyzer software packages and especially part of HamAlyzer.
Here you can see a HI FI Audio signal compared to a typical signal. The HI
FI signal is in light
blue and the
normal signal is in green.
You can easily see how much useful
information could be added to the signal if the ham expressed in the green chart
just added a little to his setup to improve the quality of his audio. In
fact during the time I was taking the snapshot of his audio he was
bragging about how good he sounded. I am not making fun of this person,
but simply trying to illustrate what could be done by adjusting your audio
and how a good spectrum analyzer program can make it easier to see how you
are doing.
First you have to know
what your audio signal sounds like, by monitoring yourself as you speak
through the monitor in your rig. Use a good set of headphones when doing
this. Turn up the volume to where it is a little uncomfortable and listen.
Do you like what you hear? Does it sound like what you want to sound like?
Is there sufficient lows and highs? Remember you are the only one who
matters. Is there a lot of extra noise coming on the air with you, like
fans, computers, or sounds from other parts of your home? If you hear
anything you are not proud of, you can work to put out an audio
presentation to your fellow hams that you will like.
Hooking up your radio to
a computer sound card is not that hard and can be as easy as getting a
cable at Radio Shack. Be sure you know what size and type of plugs you are
working with. Most sound cards use 1/8 plugs. Some radios also use 1/8
plugs, but you may have to take the audio out of DIN plug, so check before
you go to get the cable. You can take the audio from the fixed output on
the back of most radios or even take it out of the speaker jack. You could
also do it a little cleaner as I describe on this page in setting up to
record. Click
here to go to that description and discussion.
By the way if you
come out of the speaker jack, be sure not to overload the line input of
your sound card. It is not a fixed low level output and if the volume is
up to high you will have problems. You will probably not do any real
damage, but you will get a distorted reading of your audio. Don't use the
mic input of the sound card unless that is the only port you have on the
card. Most sound cards have both line and mic inputs.
Get and install a
Spectral Analysis software program like the one I am using by the name of
HamAlyzer.
Click
HERE
to go to the web page and at
least get the demo copy which has all the functions turned on for a 10 day
FREE trial.
I
have no financial interest in this software or it's author. I simple
believe it is the best software for all hams interested in good
audio, unless you are a pro audio engineer with a lot of money. If you are
one of those individuals, then maybe one of the other packages
available that I mention on other parts of this page, will be for you.
Even if you do not get
the Analyzer software and monitor your signal that way, you can make
improvements by doing and getting just a few things. Set up your radio
correctly. Go to other parts of this page to see how to do that. If your
rig has setup menus, know about them and use them. Get a better microphone
that will pass all the frequency that your rig is capable of passing. You
would think that the mic that came with your rig would do that, but they
don't always. Some hams are using the old mic that they got at a flea
market 30 years ago on a $3,000 new DSP rig. Not a good idea. Look at
reducing the ambient noise in your shack. Maybe get an outboard noise
gate. Make sure your mic gain is set correctly and if you use processing,
make sure it is setup correctly? Many hams use the compressors in their
rigs to project more audio, but this may not be the best way to do it
under rag chew conditions. Maybe for DXing when the conditions are
different, but you would not want to listen to someone that sounds like
that for very long.
There are many, many
ways to make the above chart look better with external audio gear. I
cover all that stuff in other parts of this page. Go back to the
"Audio Setup" pages and check it out. It is not really
that expensive or difficult. By using outboard audio gear like equalizers
(EQ), noise gates, compressors, and special effects boxes (FX), you can
use Spectrum Analyzers to expand the range of your audio and take some of
the peaks and valleys out of your signal as was shown in the above fig
1. In that example, you would look at the chart and boost, or cut
the frequencies as indicated. On a graphic equalizer, one with sliders
like most home HI FI equipment, you would move the corresponding slider up
or down until the chart was smoothed out. On a parametric equalizer you
would adjust the frequency, bandwidth, and gain. You could then apply some
FX (effects) like some reverb, and polish your audio signal. Of course
this is all up to your own personal goals and you do not have to have any
of these boxes to sound better. As I said before, I could make most rigs
sound just great and have a nice smooth chart with very few dips and
spikes with all the bandwidth that my rig could provide for between $200
and $300.
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